OpenLog

Components & Accessories Tools
1

I have 2 Sparkfun OpenLog units both of which act the same way. They are connected to GPSs through the UART connection, 5 Volts. One uses a Sparkfun NEO-M9N and the other is connected to an M8N. The baud rate is set correctly in the config file on the SD card.

On startup one of 4 things happens, seemingly each about 25% of the time.

  1. The logger records a blank file

  2. It records a file that starts with “˜ø˜`fffà† ˜à† ˜à† xà†ff†žþž€˜”

  3. It records a file that starts with “顠悘晦†蘘頀ᣠ†砘蛠晦ᢆ鸆黾ڀ˜惦頀ᢞ”

  4. It records a file with the correct NMEA text output.

What can I do to help the situation?

Thanks!

2

The OpenLog is a 3.3V device, and the inputs must not be exposed to 5V. You need a level shifter of some sort between a 5V TX output and the 3.3V RX input. A 4.7K series resistor works, and is probably safe.